This is the ProTek R/C 2S 4000mAh, 20C Lithium Polymer battery pack. This pack has T-Style Ultra connectors pre-installed, and comes with a 3-pin Align/E-Flite style balance connector. This battery is a great receiver battery for helicopters and airplanes!

Unlike most other Lithium Polymer batteries, these batteries can be charged at up to 2 times the rated current, or 2C! If your charger is capable, you can charge these batteries at 8A!

Specifications:

Type: Lithium Polymer

Capacity: 4000 mAh

Voltage: 7.4V nominal

Connector Type: T-Style Ultra (14 GA Wire)

Balancer Type: Align/E-Flite compatible (XH)

Number of Cells: 2

Weight: 204g

Configuration: 2S1P

Dimensions (WxLxH): 41 x 135 x 19mm

Maximum Charge Rate: 2C (8A)!

Maximum Continuous Discharge: 20C (80A)

Maximum Burst Discharge: 40C (160A) for 3 seconds

IMPORTANT:
1) DO NOT leave the battery in your model when charging
2) DO NOT leave unattended when charging
3) ALWAYS balance charge the battery
4) ALWAYS use a LiPo charging bag
5) YOU MUST use a Li-Poly specific charger to charge the pack (NiMH or NiCD only chargers WILL NOT WORK!)
6) YOU MUST not over discharge the Li-Poly battery pack
7) READ & UNDERSTAND the instructions carefully before operating this battery

NOTE: When using high energy Li-Polymer Batteries, please do not over-discharge or over-charge batteries as this will result in over heated batteries. Discharging capacity can't exceed 80% of the max capacity of the pack after full charging to ensure a good cycle performance. It is recommended to fully charge a brand new battery before using and only discharge the battery 50% for first 5 cycles. Always monitor race time and/or set a low voltage warning on ESC (End voltage cannot be lower than 3.2v per cell) Do not use the battery that has too low a voltage.

Do not expose batteries to sunshine or store/charge batteries at the temperature above 35°C or in a closed car. The high temperature environment could cause damage to the pack or make it burst. If the battery becomes hot while fast charging, high current discharging or racing, do not charge the battery until it has cooled completely. Wait about 20 mins, then inspect prior to recharging.